Merge tag 'renesas-clk-for-v5.14-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into clk-renesas

Pull Renesas clk driver updates from Geert Uytterhoeven:

 - Add support for CPU core clock boost modes on R-Car Gen3
 - Add ISPCS (Image Signal Processor) clocks on R-Car V3U
 - Switch SH/R-Mobile and R-Car "DIV6" clocks to .determine_rate()
   and improve support for multiple parents
 - Switch RZ/N1 divider clocks to .determine_rate()
 - Add ZA2 (Audio Clock Generator) clock on R-Car D3
 - Minor fixes and improvements

* tag 'renesas-clk-for-v5.14-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers:
  clk: renesas: r8a77995: Add ZA2 clock
  clk: renesas: cpg-mssr: Make srstclr[] comment block consistent
  clk: renesas: cpg-mssr: Remove unused [RM]MSTPCR() definitions
  clk: renesas: r9a06g032: Switch to .determine_rate()
  clk: renesas: div6: Implement range checking
  clk: renesas: div6: Consider all parents for requested rate
  clk: renesas: div6: Switch to .determine_rate()
  clk: renesas: div6: Simplify src mask handling
  clk: renesas: div6: Use clamp() instead of clamp_t()
  clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()
  clk: renesas: r8a779a0: Add ISPCS clocks
  clk: renesas: rcar-gen3: Add boost support to Z clocks
  clk: renesas: rcar-gen3: Add custom clock for PLLs
  clk: renesas: rcar-gen3: Increase Z clock accuracy
  clk: renesas: rcar-gen3: Grammar s/dependent of/dependent on/
  clk: renesas: rcar-gen3: Remove superfluous masking in cpg_z_clk_set_rate()
  clk: renesas: rcar-gen3: Make cpg_z_clk.mask u32
  clk: renesas: rcar-gen3: Update Z clock rate formula in comments

Author: bebarino

drivers/clk/renesas/clk-div6.c

@@ -28,17 +28,15 @@
  * @hw: handle between common and hardware-specific interfaces
  * @reg: IO-remapped register
  * @div: divisor value (1-64)
- * @src_shift: Shift to access the register bits to select the parent clock
- * @src_width: Number of register bits to select the parent clock (may be 0)
+ * @src_mask: Bitmask covering the register bits to select the parent clock
  * @nb: Notifier block to save/restore clock state for system resume
  * @parents: Array to map from valid parent clocks indices to hardware indices
  */
 struct div6_clock {
 	struct clk_hw hw;
 	void __iomem *reg;
 	unsigned int div;
-	u32 src_shift;
-	u32 src_width;
+	u32 src_mask;
 	struct notifier_block nb;
 	u8 parents[];
 };
@@ -99,15 +97,52 @@ static unsigned int cpg_div6_clock_calc_div(unsigned long rate,
 		rate = 1;
 
 	div = DIV_ROUND_CLOSEST(parent_rate, rate);
-	return clamp_t(unsigned int, div, 1, 64);
+	return clamp(div, 1U, 64U);
 }
 
-static long cpg_div6_clock_round_rate(struct clk_hw *hw, unsigned long rate,
-				      unsigned long *parent_rate)
+static int cpg_div6_clock_determine_rate(struct clk_hw *hw,
+					 struct clk_rate_request *req)
 {
-	unsigned int div = cpg_div6_clock_calc_div(rate, *parent_rate);
+	unsigned long prate, calc_rate, diff, best_rate, best_prate;
+	unsigned int num_parents = clk_hw_get_num_parents(hw);
+	struct clk_hw *parent, *best_parent = NULL;
+	unsigned int i, min_div, max_div, div;
+	unsigned long min_diff = ULONG_MAX;
+
+	for (i = 0; i < num_parents; i++) {
+		parent = clk_hw_get_parent_by_index(hw, i);
+		if (!parent)
+			continue;
+
+		prate = clk_hw_get_rate(parent);
+		if (!prate)
+			continue;
+
+		min_div = max(DIV_ROUND_UP(prate, req->max_rate), 1UL);
+		max_div = req->min_rate ? min(prate / req->min_rate, 64UL) : 64;
+		if (max_div < min_div)
+			continue;
+
+		div = cpg_div6_clock_calc_div(req->rate, prate);
+		div = clamp(div, min_div, max_div);
+		calc_rate = prate / div;
+		diff = calc_rate > req->rate ? calc_rate - req->rate
+					     : req->rate - calc_rate;
+		if (diff < min_diff) {
+			best_rate = calc_rate;
+			best_parent = parent;
+			best_prate = prate;
+			min_diff = diff;
+		}
+	}
+
+	if (!best_parent)
+		return -EINVAL;
 
-	return *parent_rate / div;
+	req->best_parent_rate = best_prate;
+	req->best_parent_hw = best_parent;
+	req->rate = best_rate;
+	return 0;
 }
 
 static int cpg_div6_clock_set_rate(struct clk_hw *hw, unsigned long rate,
@@ -133,11 +168,11 @@ static u8 cpg_div6_clock_get_parent(struct clk_hw *hw)
 	unsigned int i;
 	u8 hw_index;
 
-	if (clock->src_width == 0)
+	if (clock->src_mask == 0)
 		return 0;
 
-	hw_index = (readl(clock->reg) >> clock->src_shift) &
-		   (BIT(clock->src_width) - 1);
+	hw_index = (readl(clock->reg) & clock->src_mask) >>
+		   __ffs(clock->src_mask);
 	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
 		if (clock->parents[i] == hw_index)
 			return i;
@@ -151,18 +186,13 @@ static u8 cpg_div6_clock_get_parent(struct clk_hw *hw)
 static int cpg_div6_clock_set_parent(struct clk_hw *hw, u8 index)
 {
 	struct div6_clock *clock = to_div6_clock(hw);
-	u8 hw_index;
-	u32 mask;
+	u32 src;
 
 	if (index >= clk_hw_get_num_parents(hw))
 		return -EINVAL;
 
-	mask = ~((BIT(clock->src_width) - 1) << clock->src_shift);
-	hw_index = clock->parents[index];
-
-	writel((readl(clock->reg) & mask) | (hw_index << clock->src_shift),
-	       clock->reg);
-
+	src = clock->parents[index] << __ffs(clock->src_mask);
+	writel((readl(clock->reg) & ~clock->src_mask) | src, clock->reg);
 	return 0;
 }
 
@@ -173,7 +203,7 @@ static const struct clk_ops cpg_div6_clock_ops = {
 	.get_parent = cpg_div6_clock_get_parent,
 	.set_parent = cpg_div6_clock_set_parent,
 	.recalc_rate = cpg_div6_clock_recalc_rate,
-	.round_rate = cpg_div6_clock_round_rate,
+	.determine_rate = cpg_div6_clock_determine_rate,
 	.set_rate = cpg_div6_clock_set_rate,
 };
 
@@ -236,17 +266,15 @@ struct clk * __init cpg_div6_register(const char *name,
 	switch (num_parents) {
 	case 1:
 		/* fixed parent clock */
-		clock->src_shift = clock->src_width = 0;
+		clock->src_mask = 0;
 		break;
 	case 4:
 		/* clock with EXSRC bits 6-7 */
-		clock->src_shift = 6;
-		clock->src_width = 2;
+		clock->src_mask = GENMASK(7, 6);
 		break;
 	case 8:
 		/* VCLK with EXSRC bits 12-14 */
-		clock->src_shift = 12;
-		clock->src_width = 3;
+		clock->src_mask = GENMASK(14, 12);
 		break;
 	default:
 		pr_err("%s: invalid number of parents for DIV6 clock %s\n",

drivers/clk/renesas/r8a77995-cpg-mssr.c

@@ -75,6 +75,7 @@ static const struct cpg_core_clk r8a77995_core_clks[] __initconst = {
 	DEF_RATE(".oco",       CLK_OCO,            8 * 1000 * 1000),
 
 	/* Core Clock Outputs */
+	DEF_FIXED("za2",       R8A77995_CLK_ZA2,   CLK_PLL0D3,     2, 1),
 	DEF_FIXED("z2",        R8A77995_CLK_Z2,    CLK_PLL0D3,     1, 1),
 	DEF_FIXED("ztr",       R8A77995_CLK_ZTR,   CLK_PLL1,       6, 1),
 	DEF_FIXED("zt",        R8A77995_CLK_ZT,    CLK_PLL1,       4, 1),

drivers/clk/renesas/r8a779a0-cpg-mssr.c

@@ -180,6 +180,10 @@ static const struct mssr_mod_clk r8a779a0_mod_clks[] __initconst = {
 	DEF_MOD("i2c4",		522,	R8A779A0_CLK_S1D4),
 	DEF_MOD("i2c5",		523,	R8A779A0_CLK_S1D4),
 	DEF_MOD("i2c6",		524,	R8A779A0_CLK_S1D4),
+	DEF_MOD("ispcs0",	612,	R8A779A0_CLK_S1D1),
+	DEF_MOD("ispcs1",	613,	R8A779A0_CLK_S1D1),
+	DEF_MOD("ispcs2",	614,	R8A779A0_CLK_S1D1),
+	DEF_MOD("ispcs3",	615,	R8A779A0_CLK_S1D1),
 	DEF_MOD("msi0",		618,	R8A779A0_CLK_MSO),
 	DEF_MOD("msi1",		619,	R8A779A0_CLK_MSO),
 	DEF_MOD("msi2",		620,	R8A779A0_CLK_MSO),

drivers/clk/renesas/r9a06g032-clocks.c

@@ -604,20 +604,19 @@ r9a06g032_div_clamp_div(struct r9a06g032_clk_div *clk,
 	return div;
 }
 
-static long
-r9a06g032_div_round_rate(struct clk_hw *hw,
-			 unsigned long rate, unsigned long *prate)
+static int
+r9a06g032_div_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
 {
 	struct r9a06g032_clk_div *clk = to_r9a06g032_div(hw);
-	u32 div = DIV_ROUND_UP(*prate, rate);
+	u32 div = DIV_ROUND_UP(req->best_parent_rate, req->rate);
 
 	pr_devel("%s %pC %ld (prate %ld) (wanted div %u)\n", __func__,
-		 hw->clk, rate, *prate, div);
+		 hw->clk, req->rate, req->best_parent_rate, div);
 	pr_devel("   min %d (%ld) max %d (%ld)\n",
-		 clk->min, DIV_ROUND_UP(*prate, clk->min),
-		clk->max, DIV_ROUND_UP(*prate, clk->max));
+		 clk->min, DIV_ROUND_UP(req->best_parent_rate, clk->min),
+		 clk->max, DIV_ROUND_UP(req->best_parent_rate, clk->max));
 
-	div = r9a06g032_div_clamp_div(clk, rate, *prate);
+	div = r9a06g032_div_clamp_div(clk, req->rate, req->best_parent_rate);
 	/*
 	 * this is a hack. Currently the serial driver asks for a clock rate
 	 * that is 16 times the baud rate -- and that is wildly outside the
@@ -630,11 +629,13 @@ r9a06g032_div_round_rate(struct clk_hw *hw,
 	if (clk->index == R9A06G032_DIV_UART ||
 	    clk->index == R9A06G032_DIV_P2_PG) {
 		pr_devel("%s div uart hack!\n", __func__);
-		return clk_get_rate(hw->clk);
+		req->rate = clk_get_rate(hw->clk);
+		return 0;
 	}
+	req->rate = DIV_ROUND_UP(req->best_parent_rate, div);
 	pr_devel("%s %pC %ld / %u = %ld\n", __func__, hw->clk,
-		 *prate, div, DIV_ROUND_UP(*prate, div));
-	return DIV_ROUND_UP(*prate, div);
+		 req->best_parent_rate, div, req->rate);
+	return 0;
 }
 
 static int
@@ -663,7 +664,7 @@ r9a06g032_div_set_rate(struct clk_hw *hw,
 
 static const struct clk_ops r9a06g032_clk_div_ops = {
 	.recalc_rate = r9a06g032_div_recalc_rate,
-	.round_rate = r9a06g032_div_round_rate,
+	.determine_rate = r9a06g032_div_determine_rate,
 	.set_rate = r9a06g032_div_set_rate,
 };